Conversion of biomass

ABSTRACT

Biomass feedstocks (e.g., plant biomass, animal biomass, and municipal waste biomass) are processed to produce useful products, such as fuels. For example, systems are described that can convert feedstock materials to a sugar solution, especially, xylose, which can then be chemically converted to furfural and furfural-derived products.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 61/667,481, filed Jul. 03, 2012. The complete disclosure of thisprovisional application is hereby incorporated by reference herein.

Various carbohydrates, such as cellulosic and lignocellulosic materials,e.g., in fibrous form, are produced, processed, and used in largequantities in a number of applications. Often such materials are usedonce, and then discarded as waste, or are simply considered to be wastematerials, e.g., sewage, bagasse, sawdust, and stover.

Various cellulosic and lignocellulosic materials, their uses, andapplications have been described in U.S. Pat. Nos. 7,846,295, 7,307,108,7,074,918, 6,448,307, 6,258,876, 6,207,729, 5,973,035 and 5,952,105; andin various patent applications, including “FIBROUS MATERIALS ANDCOMPOSITES,” PCT/US20061010648, filed on Mar. 23, 2006, “FIBROUSMATERIALS AND COMPOSITES,” U.S. Patent Publication No. 2007/0045456 AND“SACCHARIFYING BIOMASS”, U.S. patent application Ser. Nos. 12/704,515.12/417,720.

BACKGROUND OF THE INVENTION SUMMARY

Generally, this invention relates to processes for converting acellulosic, starchy or lignocellulosic feedstock to useful products,organic sugar derived products for example, furfural andfurfural-derived products.

Xylose can be chemically converted into many useful intermediates andproducts. The intermediates and products include but are not limited tofurfural, furfuryl alcohol, methyl furan, methyl tetrahydrofuran, furan,tetrahydrofuran and similar structures. Xylose is shown in itshemiacetal structure as I. Xylose can exist in various differentchemical forms.

The conversion can be by chemically converting the xylose the product orthe intermediate. The xylose can be chemically converted, for example,by any one or more of cyclization reactions, polymerization reactions,condensation reactions, reduction reactions, oxidation reactions,esterification reactions, alkylation reactions, and combinationsthereof. The product of the conversion can be, for example, furfural.Optionally, the product and the intermediates can be isolated (e.g., bychromatography, crystallization, precipitation, filtering,centrifugation, evaporation, extraction, distillation, phase separation,heating, vacuum distillation or combinations of these)

For instance, in the case of chemically converting xylose to furfural;furfural can be a product or an intermediate that can be, in turn,converted to wide array of products including but not limited tofurfuryl alcohol, methyl furan, furan, methyl tetrahydrofuran andtetrahydrofuran. In some cases, converting can be by reacting the xyloseor the chemical intermediate with an acid catalyst. Thus, for example,xylose can be dehydrated, losing 3 moles of water, to give furfural andthe furfural can be hydrogenated to furfuryl alcohol. Optionally, theacid catalyst can be selected for example from acidified Zeolites,acidified silica, surface grafted silicas, acid clays, functionalizedmesoporous silicas, poly acids, acid functionalized polymers, polysulfonic acids, Nafion® perfluorinated sulfonic acid resin or membrane,poly acetic acids, poly phosphonic acids, polystyrene sulfonic acids,tetraorthosilicates, 3-(mercaptopropyl) trimethoxysilane, Lewis acids,microporous silicoaluminaphosphate, metal oxides, ZrO₂, Al₂O₃, TiO₂,SiO₂, V₂O₃, sulfate salts, (NH₄)₂SO₄, metal halides, MgCl₂, LaCl₃,FeCl₃, metal carbonates, Cs₂CO₃, ionic liquids, Tungsten oxides,Tungstate, Phosphoric acid, Phosphonic acid, sulfuric acid, hydrochloricacid, nitric acid and combinations thereof.

In some cases, the methods include heating the xylose (e.g., to at least50° C., at least 60° C., at least 70° C., at least 80° C. at least 90°C., at least 100° C., at least, 120° C. at least 140° C., at least 160°C., at least 180° C., at least 200° C., at least 220° C., at least 240°C., at least 260° C. or at least 280° C. or at least 300° C., e.g.,between 200 and 320° C., between 250 and 300° C., between 260 and 290°C.), and/or subjecting the same to greater than atmospheric pressure(e.g., at least 10 psi, at least 100 psi, at least 500 psi, at least1000psi, at least 5000 psi, at least 12000 psi, e.g., between 10 and12000 psi). The pressure can be derived from the autogenous pressuregenerated by temperatures, but also by added pressure from added gasessuch as nitrogen.

In some aspects xylose is transformed, e.g., chemically, to afurfural-derived product. For example, transforming can comprise achemical reaction selected from the group consisting of, a reductionreaction, a decarbonylation reaction, a de-aromatization reaction, apolymerization reaction or combinations thereof. The furfural-derivedproduct can be furfuryl alcohol, methytetrahydrofuran, furan,tetrahydrofuran, furancarboxaldehyde, poly(furfuryl alcohol), apolyether or combinations of these. The products include all possiblestereoisomers including those that can be obtained by chemicalconversions of prochiral centers. For example, the conversion offurfuryl alcohol to tetrahydrofurfuryl alcohol results in a product witha stereocenter at the alpha carbon. Thus, both stereoisomers can bemade.

The processes disclosed herein include saccharification of thefeedstock, and transportation of the feedstock from a remote location,e.g., where the feedstock is produced or stored, to the manufacturingfacility. In some cases, saccharification can take place partially orentirely during transport. In some implementations, the process furtherincludes reducing the recalcitrance of the feedstock, ⁻before or duringsaccharification. The process may include the further steps of measuringthe lignin content of the feedstock and determining whether pretreatmentis needed and under what conditions based on the measured lignincontent.

Many of the methods described herein can provide cellulosic and/orlignocellulosic materials that have, for example, a lower recalcitrancelevel, a lower molecular weight, a different level of functionalizationand/or crystallinity relative to a native material. Many of the methodsprovide materials that can be more readily utilized by a variety ofmicroorganisms, such as one or more homoacetogens or heteroacetogens(with or without enzymatic hydrolysis assistance) to produce usefulproducts, such as energy, fuels, foods, sugars (e.g., xylose andglucose), organic products (e.g., derived from sugars), and materials.In addition, to the furfural product describe above examples of productsthat can be derived from sugars include, but are not limited to,polyethers, hydrogen, alcohols (e.g., monohydric alcohols or dihydricalcohols, such as ethanol, n-propanol, iso-propanol, propylene glycol,1,4-butanediol, 1,3-propanediol, methyl or ethyl esters of any of thesealcohols), biodiesel, organic acids (e.g., acetic acid and/or lacticacid), hydrocarbons, co-products (e.g., proteins, such as cellulolyticproteins (enzymes) or single cell proteins), and mixtures of any ofthese. Other examples include carboxylic acids, such as acetic acid orbutyric acid, salts of a carboxylic acid, a mixture of carboxylic acidsand salts of carboxylic acids and esters of carboxylic acids (e.g.,methyl, ethyl and n-propyl esters), ketones, aldehydes, alpha, betaunsaturated acids, such as acrylic acid and olefins, such as ethylene.Other products include methyl acrylate, methyl methacrylate, lacticacid, propionic acid, butyric acid, succinic acid, 3-hydroxypropionicacid, a salt of any of the acids and a mixture of any of the acids andrespective salts.

Other intermediates and products, including food and pharmaceuticalproducts, are described in U.S. application Ser. No. 12/417,723, filedApr. 3, 2009; the full disclosure of which is hereby incorporated byreference herein in its entirety.

Some of the products obtained by the methods disclosed herein, can beused directly or as a chemical intermediate to a solvent (e.g., forrefining lubricating oils), as a fungicide, as a weed killer, astransportation fuels, nylon, lubricants, solvents, adhesives, medicines,resin and plastics. Many of the products obtained by the methodsdisclosed herein, such as ethanol or n-butanol, can be utilized directlyas a fuel or as a blend with other components, such as gasoline, forpowering cars, trucks, tractors, ships or trains, e.g., as an internalcombustion fuel or as a fuel cell feedstock. Other products (e.g.,organic acids, such as acetic acid and/or lactic acid) can be convertedto other moieties (e.g., esters or anhydrides) that can be converted andutilized as a fuel. Many of the products obtained can also be utilizedto power watercraft and aircraft, such as planes, e.g., having jetengines, or helicopters. In addition, the products described herein canbe utilized for electrical power generation, e.g., in a conventionalsteam generating plant or in a fuel cell plant.

In one aspect, the invention features a method including providing acellulose, hemicellulose and/or lignocellulose-containing feedstock(e.g., a biomass that includes polysaccharides of glucose, xylose andother saccharides), mixing the feedstock with a solvent, such as water,and an agent, such as a saccharifying enzyme or acid, and optionallytransporting the resulting mixture. Suitable acids include mineralacids, e.g., sulfuric acid or hydrochloric acid.

In one aspect, the invention features a method for converting a sugar,including converting xylose to a product or intermediate, the xylosebeing obtained by treating biomass with any one or more of sonication,irradiation, pyrolysis, oxidation, and saccharification. For example thebiomass can be irradiated and then saccharified.

The invention can feature xylose that is derived from the treatedmaterial by a process including hydrolysis of the treated material.Hydrolysis can include contacting the treated biomass material with atleast one of an acid, a base, heat, microwave energy, sonic energy,mechanical energy, shearing, milling or an enzyme. For example, thexylose can be derived from contacting material treated with at least oneof oxidation, sonication, irradiation, pyrolysis and/or with at leastone xylanase.

The methods can include producing glucose. Optionally the glucose andxylose are separated prior to converting the xylose to a product. Alsooptionally, the glucose can be fermented and then the xylose convertedto an intermediate or a product.

The biomass used in the methods herein described can includehemicellulose xylan, glucuronoxylan, arabinoxylan, glucomannan andxyloglucan). The biomass can be selected from one or more of paper,paper products, paper waste, wood, particle board, sawdust, agriculturalwaste, sewage, silage, grasses, wheat straw, rice hulls, bagasse,cotton, jute, hemp, tiax, bamboo, sisal, abaca, straw, corn cobs, cornstover, alfalfa, hay, coconut hair, seaweed, algae, and mixturesthereof.

In some aspects the method includes irradiating the biomass prior tosaccharification with between 10 and 200 Mrad. Optionally, theirradiating can be 10 and 75 Mrad, or 20 and 50 Mrad. Additionally, theirradiation is provided by an electron beam (e.g., from an electronaccelerator), for example, with an electron beam power between 0.5 and10 MeV (e.g., 0.5-2 MeV), Typical electron beam irradiation device powercan be 50 kW to 500 kW, or 75 kW to 250 kW.

The method can also include reducing the recalcitrance of the feedstockprior to mixing the feedstock with the solvent and enzyme, e.g., bytreating the feedstock with a physical treatment. The physical treatmentcan be, for example, selected from the group consisting of mechanicaltreatment, radiation, sonication, pyrolysis, oxidation, steam explosion,chemical treatment, and combinations thereof. Chemical treatment mayinclude the use of a single chemical or two or more chemicals.Mechanical treatments include, for example, cutting, milling, pressing,grinding, shearing and chopping. Milling may include, for example, ballmilling, hammer milling, or other types of milling.

The physical treatment can comprise any one or more of the treatmentsdisclosed. Herein, applied alone or in any desired combination, andapplied once or multiple times. In some cases, the physical treatmentcan comprise irradiating with ionizing radiation, alone or accompaniedby mechanical treatment before and/or after irradiation. Irradiation canbe performed, for example, with an electron beam.

In some cases, the method includes mechanically treating the feedstockto reduce the bulk density of the feedstock and/or increase the surfacearea of the feedstock, e.g., by performing a shearing process on thefeedstock. In some embodiments, after mechanical treatment the materialhas a bulk density of less than 0.6 g/cm³, 0.5 g/cm³ , 0.4 g/cm³ 0.25g/cm³, e.g., 0.20 g/cm³, 0.15 g/cm³, 0.10 g/cm³, 0.05 g/cm³or less,e.g., 0.025 g/cm³. Bulk density is determined using ASTM D 1895B.Briefly, the method involves filling a measuring cylinder of knownvolume with a sample and obtaining a weight of the sample. The bulkdensity is calculated by dividing the weight of the sample in grams bythe known volume of the cylinder in cubic centimeters. If desired,irradiated or mechanically treated or untreated biomass can be densifiedto 0.15 to 0.8 g/cm³, 0.25 to 0.7 g/cm³ or 0.25 to 0.6 g/cm¹

In yet another aspect, the invention features a sugar concentrate madeby saccharifying a dispersion that includes between about 10 percent byweight and about 90 percent by weight of a cellulosic or lignocellulosicmaterial and converting this to another intermediate or product (e.g.,furfural and furfural derived products).

In some implementations, one or more components of the processingequipment, for example the mechanical treatment equipment, chemical(e.g., acid or base) treatment equipment, irradiating equipment,sonicating, pyrolyzing, oxidizing, steam exploding, saccharifying and/orfermenting equipment, or any of the other equipment described herein,may be portable, e.g., in the manner of the mobile processing equipmentdescribed in U.S. patent application Ser. No. 12/374,549, and PublishedInternational Application No. WO 2008/011598, the full disclosures ofwhich are incorporated herein by reference.

Changing a molecular structure of a material or molecules (e.g.,molecules that are part of the material), as used herein, means tochange the chemical bonding arrangement or conformation of thestructure. For example, the change in the molecular structure caninclude changing the supramolecular structure of the material, oxidationof the material or molecule (e.g., adding oxygen or removing hydrogen),reduction of the material or molecules (e.g., hydrogenation),decarbonylation of a material or molecule, changing an average molecularweight, changing an average crystallinity, changing a surface area,changing a degree of polymerization, changing a porosity, changing adegree of branching, grafting on other materials, changing a crystallinedomain size, or changing an overall domain size. A change in molecularstructure may be effected using any one or more of the physicaltreatments described herein, alone or in any combination, applied onceor repeatedly.

DESCRIPTION OF THE DRAWING

FIG. 1 is a diagram illustrating the enzymatic hydrolysis of celluloseand xylan to glucose and xylose respectively.

FIG. 2 is a flow diagram illustrating conversion of a feedstock tovarious products.

FIG. 3 is a reaction scheme showing possible organic intermediates orproducts derived from a sugar.

DETAILED DESCRIPTION

Generally, this invention relates to processes for converting acellulosic, starchy or lignocellulosic feedstock to useful products,organic sugar derived products especially xylose conversion to furfuraland furfural-derived products.

Cellulosic, hemicellulosic and lignocellulosic materials, such asbiomass (e.g., plant biomass, animal biomass, paper, and municipal wastebiomass), can be processed to a lower level of recalcitrance (ifnecessary) and converted into useful products such as those listed byway of example herein. Systems and processes are described herein thatuse readily abundant but often difficult to process cellulosic orlignocellulosic materials, e.g., municipal waste streams and waste paperstreams, such as streams that include newspaper, kraft paper, corrugatedpaper or mixtures of these. Generally, if required, materials can bephysically treated or processed using one or more of any of the methodsdescribed herein, such as mechanical treatment, chemical treatment,radiation, sonication, oxidation, pyrolysis and steam explosion.

In some cases, a manufacturing plant utilizing the processes describedherein will obtain a variety of different feedstocks in the course ofits operation. Some feedstocks may be relatively homogeneous incomposition, for example a shipment of corn cobs, while other feedstocksmay be of variable composition, for example municipal waste.

Feedstocks can include, for example, paper, paper products, wood,wood-related materials, particle board, grasses, rice hulls, bagasse,cotton, jute, hemp, flax, bamboo, wheat straw, sisal, abaca, straw, corncobs, coconut hair, algae, seaweed, altered celluloses, e.g., celluloseacetate, regenerated cellulose, and the like, or mixtures of any ofthese.

In some cases the biomass is a microbial material. Microbial sourcesinclude, but are not limited to, any naturally occurring or geneticallymodified microorganism or organism that contains or is capable ofproviding a source of carbohydrates (e.g., cellulose), for example,protists, e.g., animal protists (e.g., protozoa such as flagellates,amoeboids, ciliates, and sporozoa) and plant protists (e.g., algae suchalveolates, chlorarachniophytes, cryptomonads, euglenids, glaucophytes,haptophytes, red algae, stramenopiles, and viridaeplantae). Otherexamples include seaweed, plankton (e.g., macroplankton, mesoplankton,microplankton, nanoplankton, picoplankton, and femptoplankton),phytoplankton, bacteria (e.g., gram positive bacteria, gram negativebacteria, and extremophiles), yeast and/or mixtures of these. In someinstances, microbial biomass can be obtained from natural sources, e.g.,the ocean, lakes, bodies of water, e.g., salt water or fresh water, oron land. Alternatively or in addition, microbial biomass can be obtainedfrom culture systems, e.g., large scale dry and wet culture systems.

In order to process the feedstock to a form that can be readilyconverted the cellulose in the feedstock is hydrolyzed to low molecularcarbohydrates, such as sugars, by a saccharifying agent, e.g., by anenzyme, a process referred to as saccharification. In someimplementations, the saccharifying agent comprises an acid, e,g., amineral acid. When an acid is used, co-products may be generated thatare toxic to microorganisms, in which case the process can furtherinclude removing such co-products. Removal may be performed using anactivated carbon, e.g., activated charcoal, or other suitabletechniques.

The materials that include the cellulose are treated with the enzyme,e.g., by combining the material and the enzyme in a solvent, e.g., in anaqueous solution.

Enzymes and biomass-destroying organisms that break down biomass, suchas the cellulose, hemicellulose and/or the lignin portions of thebiomass, contain or manufacture various cellulolytic enzymes(cellulases), ligninases, xylanases, hemicellulases or various smallmolecule biomass-destroying metabolites. These enzymes may be a complexof enzymes that act synergistically to degrade crystalline cellulose,xylan or the lignin portions of biomass. Examples of cellulolyticenzymes include: endoglucanases, cellobiohydrolases, and cellobiases(β-glucosidases). Referring to FIG. 1, a cellulosic substrate isinitially hydrolyzed by endoglucanases at random locations producingoligomeric intermediates. These intermediates are then substrates forexo-splitting glucanases such as cellobiohydrolase to produce cellobiosefrom the ends of the cellulose polymer. Cellobiose is a water-soluble1,4-linked dimer of glucose. Finally cellobiase cleaves cellobiose toyield glucose. In the case of hemicellulose, xylanase (e.g.,hemicellulase) act on this biopolymer and release xylose as one of thepossible products. Hemicellulose is a class of complex polysaccharides,often components in plant cell walls, including xylose units andincludes xylan, glucuronoxylan, arabinoxylan, glucomannan andxyloglucan. Xylanase are a class of enzymes the degrade hemicellulose,e.g., degrade beta 1,4-xylan bonds, into xylose, thus breaking down thehemicellulose.

Cellulose and/or xylanase are capable of degrading biomass and may be offungal or bacterial origin. Suitable enzymes include cellulases andxylanases (hemicellulases) from the genera Bacillus, Pseudomonas,Humicola, Fusarium, Thielavia, Acremonium, Chrysosporium andTrichoderma, and include species of Humicola, Coprinus, Thielavia,Fusarium, Myceliophthora, Acremonium, Cephalosporium, Scytalidium,Penicillium or Aspergillus (see, e.g., EP 458162), especially thoseproduced by a strain selected from the species Humicola insolens(reclassified as Scytalidium thermophilum, see, e.g., U.S. Pat. No,4,435,307), Coprinus cinereus, Fusarium oxysporum, Myceliophthorathermophila, Meripilus giganteus, Thielavia terrestris, Acremonium sp.,Acremonium persicinum, Acremonium acremonium, Acremonium brachypeniurn,Acrernonium dichromosporum, Acremonium obclavatum, Acremoniumpinkertoniae, Acremonium roseogriseum, Acremonium incoloratum, andAcremonium furatum; preferably from the species Humicola insolens DSM1800, Fusarium oxysporum DSM 2672, Myceliophthora thermophila CBS117.65, Cephalosporium sp. RYM-202, Acremonium sp. CBS 478.94,Acremonium sp. CBS 265.95, Acremonium persicinum CBS 169.65, Acremoniumacremonium AHU 9519, Cephalosporium sp. CBS 535.71, Acremoniumbrachypenium CBS 866.73, Acremonium dichromosporum CBS 683.73,Acremonium obclavatum CBS 311.74. Acremonium pinkertoniae CBS 157.70,Acremonium roseogriseum CBS 134.56, Acremonium incoloratum CBS 146.62,and Acremonium furatum CBS 299.7011. Cellulolytic enzymes may also beobtained from Chrysosporium, preferably a strain of Chrysosporiumlucknowense. Additionally, Trichoderma (particularly Trichoderma virile,Trichoderma reesei, and Trichoderma koningii), alkalophilic Bacillus(see, for example, U.S. Pat. No. 3,844,890 and EP 458162), andStreptomyces (see, e.g., EP 458162) may be used.

The saccharification process can be partially or completely performed ina tank (e.g., a tank having a volume of at least 4000, 40,000, or400,000 L) in a manufacturing plant, and/or can be partially orcompletely performed in transit, e.g., in a rail car, tanker truck, orin a supertanker or the hold of a ship. The time required for completesaccharification will depend on the process conditions and the feedstockand enzyme used. If saccharification is performed in a manufacturingplant under controlled conditions, the cellulose and hemicellulose maybe substantially entirely converted to glucose and xylose in about 12-96hours. If saccharification is performed partially or completely intransit, saccharification may take longer.

It is generally preferred that the tank contents be mixed duringsaccharification, e.g., using, et mixing as described in U.S.application Ser. No. 12/782,694, filed May 18, 2010; the full disclosureof which is incorporated by reference herein.

The addition of surfactants can enhance the rate of saccharification.Examples of surfactants include non-ionic surfactants, such as apolyethylene sorbitol ester Tween™ 20 or Tween™ 80, polyethylene glycolsurfactants, ionic surfactants, or amphoteric surfactants.

It is generally preferred that the concentration of the resulting sugar(e.g. glucose and xylose) solution be relatively high, e.g., greaterthan 40%, or greater than 50, 60, 70, 80, 90 or even greater than 95% byweight. This reduces the volume to be shipped, and also inhibitsmicrobial growth in the solution. However, lower concentrations may beused, in which case it may be desirable to add an antimicrobialadditive, e.g., a broad spectrum antibiotic, in a low concentration,e.g., 50 to 150 ppm. Other suitable antibiotics include amphotericin B,ampicillin, chloramphenicol, ciprofloxacin, gentamicin, hygromycin B,kanamycin, neomycin, penicillin, puromycin, streptomycin, Virginiamycin.Antibiotics will inhibit growth of microorganisms during transport andstorage, and can be used at appropriate concentrations, e.g., between 15and 1000 ppm by weight, e.g., between 25 and 500 ppm, or between 50 and150 ppm. If desired, an antibiotic can be included even if the sugarconcentration is relatively high.

A relatively high concentration solution can be obtained by limiting theamount of water added to the feedstock with the enzyme. Theconcentration can be controlled, e.g., by controlling how muchsaccharification takes place. For example, concentration can beincreased by adding more feedstock to the solution. In order to keep thesugar that is being produced in solution, a surfactant can be added,e.g., one of those discussed above. Solubility can also be increased byincreasing the temperature of the solution. For example, the solutioncan be maintained at a temperature of 40-50° C., 60-80° C., or evenhigher.

In some embodiments, the feedstock is processed to convert it to aconvenient and concentrated solid material, e.g., in a powdered,granulate or particulate form. The concentrated material can be in apurified, or a raw, crude form. The concentrated form can have, forexample, a total sugar concentration of between about 90 percent byweight and about 100 percent by weight, e.g., 92, 94, 96 or 98 percentby weight sugar. Such a form can be particularly cost effective to ship,e.g., to a bioprocessing facility, such as a biofuel manufacturingplant. Such a form can also be advantageous to store and handle, easierto manufacture and providing an option to the biorefinery as to whichproducts to manufacture.

In some instances, the powdered, granulate or particulate material canalso include one or more of the materials, e.g., additives or chemicals,described herein, such as a nutrient, a nitrogen source, e.g., urea or apeptone, a surfactant, an enzyme, or any microorganism described herein.In some instances, all materials needed for a bin-process are combinedin the powdered, granulate or particulate material. Such a form can be aparticularly convenient form for transporting to a remote bioprocessingfacility, such as a remote biofuels manufacturing facility. Such a formcan also be advantageous to store and handle.

In some instances, the powdered, granulate or particulate material (withor without added materials, such as additives and chemicals) can betreated by any of the physical treatments described herein. For example,irradiating the powdered, granulate or particulate material can increaseits solubility and can sterilize the material so that a bioprocessingfacility can integrate the material into their process directly as maybe required.

In certain instances, the powdered, granulate or particulate material(with or without added materials, such as additives and chemicals) canbe carried in a structure or a carrier for ease of transport, storage orhandling. For example, the structure or carrier can include orincorporate a bag or liner, such as a degradable bag or liner. Such aform can be particularly useful for adding directly to a bioprocesssystem.

Referring to FIG. 2, a process for manufacturing a products from abiomass feedstock. For example, the biomass is converted bysaccharification, bioprocessing and a chemical process, e.g.,saccharification to xylose and glucose, fermentation of the glucose toan alcohol (e.g., ethanol), conversion of the un-fermented xylose to aproduct by a chemical reaction. The process, can include, for example,optionally mechanically treating the feedstock (step 210), before and/orafter this treatment, optionally treating the feedstock with anotherphysical treatment, for example irradiation, to further reduce itsrecalcitrance (step 212), saccharifying the feedstock to form a sugarsolution (e.g., glucose and xylose) (step 214), transporting, e.g., bypipeline, railcar, truck or barge, the solution (or the feedstock,enzyme and water, if saccharification is performed en route) to amanufacturing plant (step 216), and then bio-processing the treatedfeedstock to produce a desired product such as an alcohol(step 218),further processing the unfermented xylose from the fermented solution tointermediates and products by chemical reactions, e.g., by stepsincluding hydrogenation, dehydration, polymerization and/or oxidation(step 220). The individual steps of this process will be described indetail below. If desired, the steps of measuring lignin content (step222) and setting or adjusting process parameters (step 224) can beperformed at various stages of the process, for example just prior tothe process step(s) used to change the structure of the feedstock, asshown. If these steps are included, the process parameters are adjustedto compensate for variability in the lignin content of the feedstock, asdescribed in U.S. Pat. No. 8,415,122, the complete disclosure of whichis incorporated herein by reference.

The manufacturing plant can be, for example, an existing starch-based orsugar--based ethanol plant or one that has been retrofitted by removingor decommissioning the equipment upstream from the bio--processingsystem (which in a typical ethanol plant generally includes grainreceiving equipment, a hammer mill, a slurry mixer, cooking equipmentand liquefaction equipment). Thus, the feedstock received by the plantis input directly into the fermentation equipment.

Biomass Materials

The biomass can be, e.g., a cellulosic, hemicellulosic orlignocellulosic material. Such materials include paper and paperproducts (e.g., polycoated paper and Kraft paper), wood, wood-relatedmaterials, e.g., particle board, grasses, rice hulls, bagasse, jute,hemp, flax, bamboo, sisal, abaca, straw, corn cobs, wheat, wheat straw,coconut hair; and materials high in—cellulose content, e.g., cotton.Feedstocks can be obtained from virgin scrap textile materials, e.g.,remnants, post-consumer waste, e.g., rags. When paper products are usedthey can be virgin materials, e.g., scrap virgin materials, or they canbe post-consumer waste. Aside from virgin raw materials, post-consumer,industrial (e.g., offal), and processing waste (e.g., effluent frompaper processing) can also be used as fiber sources. Biomass feedstockscan also be obtained or derived from human (e.g., sewage), animal orplant wastes. Additional cellulosic and lignocellulosic materials havebeen described in U.S. Pat. Nos. 6,448,307, 6,258,876, 6,207,729,5,973,035 and 5,952,105.

In some embodiments, the biomass material includes a carbohydrate thatis or includes a material having one or more β-1,4-linkages and having anumber average molecular weight between about 3,000 and 50,000. Such acarbohydrate is or includes cellulose (II), and xylan (III) and whichare derived from (β-glucose IV) and xylose respectively throughcondensation of β(1,4)-glycosidic bonds or by condensation of β-D-xyloseunits. This linkage contrasts itself with that for α(1,4)-glycosidicbonds present in starch and other carbohydrates.

51. Starchy materials include starch itself, e.g., corn starch, wheatstarch, potato starch or rice starch, a derivative of starch, or amaterial that includes starch, such as an edible food product or a crop.For example, the starchy material can be arracacha, buckwheat, banana,barley, cassava, kudzu, oca, sago, sorghum, regular household potatoes,sweet potato, taro, yams, or one or more beans, such as favas, lentilsor peas. Blends of any two or more starchy materials are also starchymaterials.

In some cases the biomass is a microbial material. Microbial sourcesinclude, but are not limited to, any naturally occurring or geneticallymodified microorganism or organism that contains or is capable ofproviding a source of carbohydrates (e.g., cellulose), for example,protists, e.g., animal protists (e.g., protozoa such as flagellates,amoeboids, ciliates, and sporozoa) and plant protists (e.g., algae suchalveolates, chlorarachniophytes, cryptomonads, euglenids, glaucophytes,haptophytes, red algae, stramenopiles, and viridaeplantae). Otherexamples include seaweed, plankton (e.g., macroplankton, mesoplankton,microplankton, nanoplankton, picoplankton, and femptoplankton),phytoplankton, bacteria (e,g., gram positive bacteria, gram negativebacteria, and extremophiles), yeast and/or mixtures of these. In someinstances, microbial biomass can be obtained from natural sources, e.g.,the ocean, lakes, bodies of water, e.g., salt water or fresh water, oron land. Alternatively or in addition, microbial biomass can be obtainedfrom culture systems, e.g., large scale dry and wet culture systems.

Physical Treatment

Physical treatment processes can include one or more of any of thosedescribed herein, such as mechanical treatment, chemical treatment,irradiation, sonication, oxidation, pyrolysis or steam explosion.Treatment methods can be used in combinations of two, three, four, oreven all of these technologies (in any order). When more than onetreatment methods is used, the methods can be applied at the same timeor at different times. Other processes that change a molecular structureof a biomass feedstock may also be used, alone or in combination withthe processes disclosed herein.

One or more of the treatment processes described below may be includedin the recalcitrance reducing operating system discussed above.Alternatively, or in addition, other processes for reducingrecalcitrance may be included.

Mechanical Treatments

In some cases, methods can include mechanically treating the biomassfeedstock. Mechanical treatments include, for example, cutting, milling,pressing, grinding, shearing and chopping. Milling may include, forexample, ball milling, hammer milling, rotor/stator dry or wet milling,or other types of milling. Other mechanical treatments include, e.g.,stone grinding, cracking, mechanical ripping or tearing, pin grinding orair attrition milling.

Mechanical treatment can be advantageous for “opening up,” “stressing,”breaking and shattering the cellulosic or lignocellulosic materials,making the cellulose of the materials more susceptible to chain scissionand/or reduction of crystallinity. The open materials can also be moresusceptible to oxidation when irradiated.

In some cases, the mechanical treatment may include an initialpreparation of the feedstock as received, e.g., size reduction ofmaterials, such as by cutting, grinding, shearing, pulverizing orchopping. For example, in some cases, loose feedstock (e.g., recycledpaper, starchy materials, or switchgrass) is prepared by shearing orshredding.

Alternatively, or in addition, the feedstock material can be physicallytreated by one or more of the other physical treatment methods, e.g.,chemical treatment, radiation, sonication, oxidation, pyrolysis or steamexplosion, and then mechanically treated. This sequence can beadvantageous since materials treated by one or more of the othertreatments, e.g., irradiation or pyrolysis, tend to be more brittle and,therefore, it may be easier to further change the molecular structure ofthe material by mechanical treatment.

In some embodiments, the feedstock material is in the form of a fibrousmaterial, and mechanical treatment includes shearing to expose fibers ofthe fibrous material. Shearing can be performed, for example, using arotary knife cutter. Other methods of mechanically treating thefeedstock include, for example, milling or grinding. Milling may beperformed using, for example, a hammer mill, ball mill, colloid mill,conical or cone mill, disk mill, edge mill, Wiley mill or grist mill.Grinding may be performed using, for example, a stone grinder, pingrinder, coffee grinder, or burr grinder. Grinding may be provided, forexample, by a reciprocating pin or other element, as is the case in apin mill. Other mechanical treatment methods include mechanical rippingor tearing, other methods that apply pressure to the fibers, and airattrition milling. Suitable mechanical treatments further include anyother technique that changes the molecular structure of the feedstock.

If desired, the mechanically treated material can be passed through ascreen, e.g., having an average opening size of 1.59 mm or less (1/16inch, 0.0625 inch). In some embodiments, shearing, or other mechanicaltreatment, and screening are performed concurrently. For example, arotary knife cutter can be used to concurrently shear and screen thefeedstock. The feedstock is sheared between stationary blades androtating blades to provide a sheared material that passes through ascreen, and is captured in a bin. The bin can have a pressure belownominal atmospheric pressure, e.g., at least 10 percent below nominalatmospheric pressure, e.g., at least 25 percent below nominalatmospheric pressure, at least 50 percent below nominal atmosphericpressure, or at least 75 percent below nominal atmospheric pressure. Insome embodiments, a vacuum source is utilized to maintain the bin belownominal atmospheric pressure.

The cellulosic or lignocellulosic material can be mechanically treatedin a dry state (e.g., having little or no free water on its surface), ahydrated state (e.g., having up to ten percent by weight absorbedwater), or in a wet state, e.g., having between about 10 percent andabout 75 percent by weight water. The fiber source can even bemechanically treated while partially or fully submerged under a liquid,such as water, ethanol or isopropanol.

The cellulosic or lignocellulosic material can also be mechanicallytreated under a gas (such as a stream or atmosphere of gas other thanair), e.g., oxygen or nitrogen, or steam.

If desired, lignin can be removed from any of the feedstock materialsthat include lignin. Also, to aid in the breakdown of the materials thatinclude cellulose, the material can be treated prior to or duringmechanical treatment or irradiation with heat, a chemical (e.g., mineralacid, base or a strong oxidizer such as sodium hypochlorite) and/or anenzyme. For example, grinding can be performed in the presence of anacid.

Mechanical treatment systems can be configured to produce streams withspecific characteristics such as, for example, specific maximum sizes,specific length-to-width., or specific surface areas ratios. Mechanicaltreatment can increase the rate of reactions or reduce the processingtime required by opening up the materials and making them moreaccessible to processes and/or reagents, such as reagents in a solution.The bulk density of feedstocks can also be controlled using mechanicaltreatment. For example, in some embodiments, after mechanical treatmentthe material has a bulk density of less than 0.25 g/cm3, e.g., 0.20g/cm3, 0.15 g/cm3, 0.10 g/cm3, 0.05 g/cm3 or less, e.g., 0.025 g/cm3.Bulk density is determined using ASTM D1895B. Briefly, the methodinvolves filling a measuring cylinder of known volume with a sample andobtaining a weight of the sample. The bulk density is calculated bydividing the weight of the sample in grams by the known volume of thecylinder in cubic centimeters.

If the feedstock is a fibrous material the fibers of the mechanicallytreated material can have a relatively large average length-to-diameterratio (e.g., greater than 20-to-1), even if they have been sheared morethan once. In addition, the fibers of the fibrous materials describedherein may have a relatively narrow length and/or length-to-diameterratio distribution.

As used herein, average fiber widths (e.g., diameters) are thosedetermined optically by randomly selecting approximately 5,000 fibers.Average fiber lengths are corrected length-weighted lengths. BET(Brunauer, Emmett and Teller) surface areas are multi-point surfaceareas, and porosities are those determined by mercury porosimetry.

If the feedstock is a fibrous material the average length-to-diameterratio of fibers of the mechanically treated material can be, e.g.,greater than 8/1, e.g., greater than 10/1, greater than 15/1, greaterthan 20/1, greater than 25/1, or greater than 50/1. An average fiberlength of the mechanically treated material can be, e.g., between about0.5 mm and 2.5 mm, e.g., between about 0.75 mm and 1.0 mm, and anaverage width (e.g., diameter) of the second fibrous material 14 can be,e.g., between about 5 μm and 50 μm, e.g., between about 10 μm and 30 μm.68. In some embodiments, if the feedstock is a fibrous material astandard deviation of the fiber length of the mechanically treatedmaterial is less than 60 percent of an average fiber length of themechanically treated material, e.g., less than 50 percent of the averagelength, less than 40 percent of the average length, less than 25 percentof the average length, less than 10 percent of the average length, lessthan 5 percent of the average length, or even less than 1 percent of theaverage length.

In some embodiments, a BET surface area of the mechanically treatedmaterial is greater than 0.1 m²/g, e.g., greater than 0.25 m²/g, greaterthan 0.5 m²/g, greater than 1.0 m²/g, greater than 1.5 m²/g, greaterthan 1.75 m²/g, greater than 5.0 m²/g, greater than 10 m²/g, greaterthan 25 m²/g, than 35 m²/g, greater than 50 m²/g, greater than 60 m²/g,greater than 75 m²/g, greater than 100 m2/g m²/g, greater than 150 m²/g,greater than 200 m²/g, or even greater than 250 m²/g.

A porosity of the mechanically treated material can be, e.g., greaterthan 20 percent, greater than 25 percent, greater than 35 percent,greater than 50 percent, greater than 60 percent, greater than 70percent, greater than 80 percent, greater than 85 percent, greater than90 percent, greater than 92 percent, greater than 94 percent, greaterthan 95 percent, greater than 97.5 percent, greater than 99 percent, oreven greater than 99.5 percent.

In some situations, it can be desirable to prepare a low bulk densitymaterial, densify the material (e.g., to make it easier and less costlyto transport to another site), and then revert the material to a lowerbulk density state. Densified materials can be processed by any of themethods described herein, or any material processed by any of themethods described herein can be subsequently densified, e.g., asdisclosed in WO 2008/073186.

Radiation Treatment

One or more radiation processing sequences can be used to process thefeedstock, and to provide a structurally modified material whichfunctions as input to further processing steps and/or sequences.Irradiation can, for example, reduce the molecular weight and/orcrystallinity of feedstock. In some embodiments, energy deposited in amaterial that releases an electron from its atomic orbital is used toirradiate the materials. The radiation may be provided by 1) heavycharged particles, such as alpha particles or protons, 2) electrons,produced, for example, in beta decay or electron beam accelerators, or3) electromagnetic radiation, for example, gamma rays, x rays, orultraviolet rays. In one approach, radiation produced by radioactivesubstances can be used to irradiate the feedstock. In some embodiments,any combination in any order or concurrently of (1) through (3) may beutilized. In another approach, electromagnetic radiation (e.g., producedusing electron beam emitters) can be used to irradiate the feedstock.The doses applied depend on the desired effect and the particularfeedstock. For example, high doses of radiation can break chemical bondswithin feedstock components. In some instances when chain scission isdesirable and/or polymer chain functionalization is desirable, particlesheavier than electrons, such as protons, helium nuclei, argon ions,silicon ions, neon ions, carbon ions, phosphorus ions, oxygen ions ornitrogen ions can be utilized. When ring-opening chain scission isdesired, positively charged particles can be utilized for their Lewisacid properties for enhanced ring-opening chain scission. For example,when maximum oxidation is desired, oxygen ions can be utilized, and whenmaximum nitration is desired, nitrogen ions can be utilized.

In one method, a first material that is or includes cellulose having afirst number average molecular weight (first M_(N)) is irradiated, e.g.,by treatment with ionizing radiation (e.g., in the form of gammaradiation, X-ray radiation, 100 nm to 280 nm ultraviolet (UV) light, abeam of electrons or other charged particles) to provide a secondmaterial that includes cellulose having a second number averagemolecular weight (second M_(N)) lower than the first number averagemolecular weight. The second material (or the first and second material)can be combined with a microorganism (with or without enzyme treatment)that can utilize the second and/or first material or its constituentsugars or lignin to produce a fuel or other useful product that is orincludes hydrogen, an alcohol (e.g., ethanol or butanol, such as n-,sec- or t-butanol), an organic acid, a hydrocarbon or mixtures of any ofthese.

Since the second material has cellulose having a reduced molecularweight relative to the first material, and in some instances, a reducedcrystallinity as well, the second material is generally moredispersible, swellable and/or soluble in a solution containing amicroorganism and/or an enzyme. These properties make the secondmaterial more susceptible to chemical, enzymatic and/or biologicalattack relative to the first material, which can greatly improve theproduction rate and/or production level of a desired product, e.g.,ethanol. Radiation can also sterilize the materials or any media neededto bioprocess the material.

In some embodiments, the second number average molecular weight (secondM_(N)) is lower than the first number average molecular weight (firstM_(N)) by more than about 10 percent, e.g., 15, 20, 25, 30, 35, 40, 50percent, 60 percent, or even more than about 75 percent.

In some instances, the second material has cellulose that has ascrystallinity (C2) that is lower than the crystallinity (C1) of thecellulose of the first material. For example, (C2) can be lower than(C1) by more than about 10 percent, e,g., 15, 20, 25, 30, 35, 40, oreven more than about 50 percent.

In some embodiments, the starting crystallinity index (prior toirradiation) is from about 40 to about 87.5 percent, e.g., from about 50to about 75 percent or from about 60 to about 70 percent, and thecrystallinity index after irradiation is from about 10 to about 50percent, e.g., from about 15 to about 45 percent or from about 20 toabout 40 percent. However, in some embodiments, e.g., after extensiveirradiation, it is possible to have a crystallinity index of lower than5 percent. In some embodiments, the material after irradiation issubstantially amorphous.

In some embodiments, the starting number average molecular weight (priorto irradiation) is from about 200,000 to about 3,200,000, e.g., fromabout 250,000 to about 1,000,000 or from about 250,000 to about 700,000,and the number average molecular weight after irradiation is from about50,000 to about 200,000, e.g., from about 60,000 to about 150,000 orfrom about 70,000 to about 125,000. However, in some embodiments, e.g.,after extensive irradiation, it is possible to have a number averagemolecular weight of less than about 10,000 or even less than about5,000.

In some embodiments, the second material can have a level of oxidation(O2) that is higher than the level of oxidation (O1) of the firstmaterial. A higher level of oxidation of the material can aid in itsdispersability, swellability and/or solubility, further enhancing thematerial's susceptibility to chemical, enzymatic or biological attack.In some embodiments, to increase the level of the oxidation of thesecond material relative to the first material, the irradiation isperformed under an oxidizing environment, e.g., under a blanket of airor oxygen, producing a second material that is more oxidized than thefirst material. For example, the second material can have more hydroxylgroups, aldehyde groups, ketone groups, ester groups or carboxylic acidgroups, which can increase its hydrophilicity.

Ionizing Radiation

Each form of radiation ionizes the carbon-containing material viaparticular interactions, as determined by the energy of the radiation.Heavy charged particles primarily ionize matter via Coulomb scattering;furthermore, these interactions produce energetic electrons that mayfurther ionize matter. Alpha particles are identical to the nucleus of ahelium atom and are produced by the alpha decay of various radioactivenuclei, such as isotopes of bismuth, polonium, astatine, radon,francium, radium, several actinides, such as actinium, thorium, uranium,neptunium, curium, californium, americium, and plutonium.

When particles are utilized, they can be neutral (uncharged), positivelycharged or negatively charged. When charged, the charged particles canbear a single positive or negative charge, or multiple charges, e.g.,one, two, three or even four or more charges. In instances in whichchain scission is desired, positively charged particles may bedesirable, in part due to their acidic nature. When particles areutilized, the particles can have the mass of a resting electron, orgreater, e.g., 500, 1000, 1500, 2000, 10,000 or even 100,000 times themass of a resting electron. For example, the particles can have a massof from about 1 atomic unit to about 150 atomic units, e.g., from aboutI atomic unit to about 50 atomic units, or from about 1 to about 25,e.g., 1, 2, 3, 4, 5, 10, 12 or 15 amu. Accelerators used to acceleratethe particles can be electrostatic DC, electrodynamic DC, RF linear,magnetic induction linear or continuous wave. For example, cyclotrontype accelerators are available from IBA, Belgium, such as theRhodotron® E-beam Accelerator system, while DC type accelerators areavailable from RDI, now IBA Industrial, such as the Dynamitron®. Ionsand ion accelerators are discussed in introductory Nuclear Physics,Kenneth S. Krane, John Wiley & Sons, Inc. (1988), Krsto Prelec, FILIKA B6 (1997) 4, 177-206, Chu, William T., “Overview of Light-Ion BeamTherapy” Columbus-Ohio, Meeting, 18-20 Mar. 2006, Iwata, Y. et al.“Alternating-Phase-Focused for Heavy-Ion Medical Accelerators”Proceedings of EPAC 2006, Edinburgh, Scotland and Leaner, C. M. et al.,“Status of the Superconducting ECR Ion Source Venus” Proceedings of EPAC2000, Vienna, Austria.

Gamma radiation has the advantage of a significant penetration depthinto a variety of materials. Sources of gamma rays include radioactivenuclei, such as isotopes of cobalt, calcium, technetium, chromium,gallium, indium, iodine, iron, krypton, samarium, selenium, sodium,thallium, and xenon.

Sources of x rays include electron beam collision with metal targets,such as tungsten or molybdenum or alloys, or compact light sources, suchas those produced. commercially by Lyncean Technologies, Inc.

Sources for ultraviolet radiation include deuterium or cadmium lamps.

Sources for infrared radiation include sapphire, zinc, or selenidewindow ceramic lamps.

Sources for microwaves include klystrons, Slevin type RF sources, oratom beam sources that employ hydrogen, oxygen, or nitrogen gases.

In some embodiments, a beam of electrons is used as the radiationsource. A beam of electrons has the advantages of high dose rates (e.g.,1, 5, or even 10 Mrad per second), high throughput, less containment,and less confinement equipment. Electrons can also be more efficient atcausing chain scission. In addition, electrons having energies of 4-10MeV can have a penetration depth of 5 to 30 mm or more, such as 40 mm.Optionally, the electrons having energies of 0.8 to 2 MeV may be used.

Electron beams can be generated, e.g., by electrostatic generators,cascade generators, transformer generators, low energy accelerators witha scanning system, low energy accelerators with a linear cathode, linearaccelerators, and pulsed accelerators. Electrons as an ionizingradiation source can be useful, e.g., for relatively thin piles ofmaterials, e.g., less than 0.5 inch, e.g., less than 0.4 inch, 0.3 inch,0.2 inch, or less than 0.1 inch. In some embodiments, the energy of eachelectron of the electron beam is from about 0.3 MeV to about 2.0 MeV(million electron volts), e.g., from about 0.5 MeV to about 1.5 MeV, orfrom about 0.7 MeV to about 1.25 MeV.

Electron beam irradiation devices may be procured commercially from IonBeam Applications, Louvain-la-Neuveee, Belgium or the Titan Corporation,San Diego, Calif. Typical electron energies can be 1 MeV, 2 MeV, 4.5MeV, 7.5 MeV, or 10 MeV. Optionally the electron energies can be 0.8 to2 MeV. Typical electron beam irradiation device power can be 1 kW, 5 kW,10 kW, 20 kW, 50 kW, 100 kW, 250 kW, or 500 kW. Additionally, electronbeam irradiation device power can be 75 to 200 kW The level ofdepolymerization of the feedstock depends on the electron energy usedand the dose applied, while exposure time depends on the power and dose.Typical doses may take values of 1 kGy, 5 kGy, 1.0 kGy, 20 kGy, 50 kGy,100 kGy, or 200 kGy.

Electron beam irradiation devices from different instrument sources maybe used. Multiple electron beam irradiation devices can be used toirradiate a biomass sample.

Ion Particle Beams

Particles heavier than electrons can be utilized to irradiate materials,such as carbohydrates or materials that include carbohydrates, e.g.,cellulosic materials, lignocellulosic materials, starchy materials, ormixtures of any of these and others described herein. For example,protons, helium nuclei, argon ions, silicon ions, neon ions, carbonions, phosphorus ions, oxygen ions or nitrogen ions can be utilized. Insome embodiments, particles heavier than electrons can induce higheramounts of chain scission (relative to lighter particles). In someinstances, positively charged particles can induce higher amounts ofchain scission than negatively charged particles due to their acidity.

Heavier particle beams can be generated, e.g., using linear acceleratorsor cyclotrons. In some embodiments, the energy of each particle of thebeam is from about 1.0 MeV/atomic unit to about 6,000 MeV/atomic unit,e.g., from about 3 MeV/atomic unit to about 4.800 MeV/atomic unit, orfrom about 10 MeV/atomic unit to about 1,000 MeV/atomic unit.

In certain embodiments, ion beams used to irradiate carbon-containingmaterials, e.g., biomass materials, can include more than one type ofion. For example, ion beams can include mixtures of two or more (e.g.,three, four or more) different types of ions. Exemplary mixtures caninclude carbon ions and protons, carbon ions and oxygen ions, nitrogenions and protons, and iron ions and protons. More generally, mixtures ofany of the ions discussed herein (or any other ions) can be used to formirradiating ion beams. In particular, mixtures of relatively light andrelatively heavier ions can be used in a single ion beam.

In some embodiments, ion beams for irradiating materials includepositively-charged ions. The positively charged ions can include, forexample, positively charged hydrogen ions (e.g., protons), noble gasions (e.g., helium, neon, argon), carbon ions, nitrogen ions, oxygenions, silicon atoms, phosphorus ions, and metal ions such as sodiumions, calcium ions, and/or iron ions. Without ‘wishing to be bound byany theory, it is believed that such positively-charged ions behavechemically as Lewis acid moieties when exposed to materials, initiatingand sustaining cationic ring-opening chain scission reactions in anoxidative environment, 95. In certain embodiments, ion beams forirradiating materials include negatively-charged ions. Negativelycharged ions can include, for example, negatively charged hydrogen ions(e.g., hydride ions), and negatively charged ions of various relativelyelectronegative nuclei (e.g., oxygen ions, nitrogen ions, carbon ions,silicon ions, and phosphorus ions). Without wishing to be bound by anytheory, it is believed that such negatively-charged ions behavechemically as Lewis base moieties when exposed to materials, causinganionic ring-opening chain scission reactions in a reducing environment.

In some embodiments, beams for irradiating materials can include neutralatoms. For example, any one or more of hydrogen atoms, helium atoms,carbon atoms, nitrogen atoms, oxygen atoms, neon atoms, silicon atoms,phosphorus atoms, argon atoms, and iron atoms can be included in beamsthat are used for irradiation of biomass materials. In general, mixturesof any two or more of the above types of atoms (e.g., three or more,four or more, or even more) can be present in the beams.

In certain embodiments, ion beams used to irradiate materials includesingly-charged ions such as one or more of H+, H−, He+, Ne+, Ar+, C+,C−, O+, O−, N+, N−, Si+, Si−, P+, P−, Na+, Ca+, and Fe+. In someembodiments, ion beams can include multiply-charged ions such as one ormore of C2+, C3+, C4+, N3+, N5+, N3−, O2+, O2−, O22−, Si2+, Si4+, Si2−,and Si4−. In general, the ion beams can also include more complexpolynuclear ions that bear multiple positive or negative charges. Incertain embodiments, by virtue of the structure of the polynuclear ion,the positive or negative charges can be effectively distributed oversubstantially the entire structure of the ions. In some embodiments, thepositive or negative charges can be somewhat localized over portions ofthe structure of the ions.

Electromagnetic Radiation

In embodiments in which the irradiating is performed withelectromagnetic radiation, the electromagnetic radiation can have, e.g.,energy per photon (in electron volts) of greater than 10² eV, e.g.,greater than 10³, 10⁴, 10⁵, 10⁶, or even greater than 10⁷ eV, In someembodiments, the electromagnetic radiation has energy per photon ofbetween 10⁴ and 10⁷, e.g., between 10⁵ and 10⁶ eV. The electromagneticradiation can have a frequency of, e.g., greater than 10¹⁶ Hz, greaterthan 10¹⁷ Hz, 10¹⁸, 10¹⁹, 10²⁰, or even greater than 10²¹ Hz. In someembodiments, the electromagnetic radiation has a frequency of between10¹⁸ and 10²² Hz, e.g., between 10¹⁹ to 10²¹ Hz.

In some embodiments, the irradiating (with any radiation source or acombination of sources) is performed until the material receives a doseof at least 0.25 Mrad, e.g., at least 1.0 Mrad, at least 2.5 Mrad, atleast 5.0 Mrad, or at least 10.0 Mrad. In some embodiments, theirradiating is performed until the material receives a dose of between1.0 Mrad and 6.0 Mrad, e.g., between 1.5 Mrad and 4.0 Mrad.

In some embodiments, the irradiating is performed at a dose rate ofbetween 5.0 and 1500.0 kilorads/hour, e.g., between 10.0 and 750.0kilorads/hour or between 50.0 and 350.0 kilorads/hours.

In some embodiments, two or more radiation sources are used, such as twoor more ionizing radiations. For example, samples can be treated, in anyorder, with a beam of electrons, followed by gamma radiation and UVlight having wavelengths from about 100 nm to about 280 nm. In someembodiments, samples are treated with three ionizing radiation sources,such as a beam of electrons, gamma radiation, and energetic UV light

Sonication

One or more sonication processing sequences can be used to processmaterials from a wide variety of different sources to extract usefulsubstances from the materials, and to provide partially degraded organicmaterial (when organic materials are employed) which functions as inputto further processing steps and/or sequences. Sonication can reduce themolecular weight and/or crystallinity of the materials, such as one ormore of any of the materials described herein, e.g., one or morecarbohydrate sources, such as cellulosic or lignocellulosic materials,or starchy materials.

In one method, a first material that includes cellulose having a firstnumber average molecular weight (first M_(n)) is dispersed in a medium,such as water, and sonicated and/or otherwise cavitated, to provide asecond material that includes cellulose having a second number averagemolecular weight (second M_(n)) lower than the first number averagemolecular weight. The second material (or the first and second materialin certain embodiments) can be combined with a microorganism (with orwithout enzyme treatment) that can utilize the second and/or firstmaterial to produce a fuel that is or includes hydrogen, an alcohol, anorganic acid, a hydrocarbon or mixtures of any of these.

Since the second material has cellulose having a reduced molecularweight relative to the first material, and in some instances, a reducedcrystallinity as well, the second material is generally moredispersible, swellable, and/or soluble in a solution containing themicroorganism, e.g., at a concentration of greater than 106microorganisms/mL. These properties make the second material moresusceptible to chemical, enzymatic, and/or microbial attack relative tothe first material, which can greatly improve the production rate and/orproduction level of a desired product, e.g., ethanol. Sonication canalso sterilize the materials, but should not be used while themicroorganisms are supposed to be alive.

In some embodiments, the second number average molecular weight (secondM_(n)) is lower than the first number average molecular weight (firstM_(n)) by more than about 10 percent, e.g., 15, 20, 25, 30, 35, 40, 50percent, 60 percent, or even more than about 75 percent.

In some instances, the second material has cellulose that has ascrystallinity (C2) that is lower than the crystallinity (C1) of thecellulose of the first material. For example, (C2) can be lower than(C1) by more than about 10 percent, e.g., 15, 20, 25, 30, 35, 40, oreven more than about 50 percent.

In some embodiments, the starting crystallinity index (prior tosonication) is from about 40 to about 87.5 percent, e.g., from about 50to about 75 percent or from about 60 to about 70 percent, and thecrystallinity index after sonication is from about 10 to about 50percent, e.g., from about 15 to about 45 percent or from about 20 toabout 40 percent. However, in certain embodiments, e.g., after extensivesonication, it is possible to have a crystallinity index of lower than 5percent. In some embodiments, the material after sonication issubstantially amorphous.

In some embodiments, the starting number average molecular weight (priorto sonication) is from about 200,000 to about 3,200,000, e.g., fromabout 250,000 to about 1,000,000 or from about 250,000 to about 700,000,and the number average molecular weight after sonication is from about50,000 to about 200,000, e.g., from about 60,000 to about 150,000 orfrom about 70,000 to about 125,000. However, in some embodiments, e.g.,after extensive sonication, it is possible to have a number averagemolecular weight of less than about 10,000 or even less than about5,000.

In some embodiments, the second material can have a level of oxidation(O2) that is higher than the level of oxidation (O1) of the firstmaterial. A higher level of oxidation of the material can aid in itsdispersability, swellability and/or solubility, further enhancing thematerial's susceptibility to chemical, enzymatic or microbial attack. Insome embodiments, to increase the level of the oxidation of the secondmaterial relative to the first material, the sonication is performed inan oxidizing medium, producing a second material that is more oxidizedthan the first material. For example, the second material can have morehydroxyl groups, aldehyde groups, ketone groups, ester groups orcarboxylic: acid groups, which can increase its hydrophilicity.

In some embodiments, the sonication medium is an aqueous medium. Ifdesired, the medium can include an oxidant, such as a peroxide (e.g.,hydrogen peroxide), a dispersing agent and/or a buffer. Examples ofdispersing agents include ionic dispersing agents, e.g., sodium laurylsulfate, and non-ionic dispersing agents, e.g., poly(ethylene glycol).

In other embodiments, the sonication medium is non-aqueous. For example,the sonication can be performed in a hydrocarbon, e.g., toluene orheptane, an ether, e.g., diethyl ether or tetrahydrofuran, or even in aliquefied gas such as argon, xenon, or nitrogen.

Pyrolysis of the Feedstock Materials

One or more pyrolysis processing sequences can be used to processcarbon-containing materials from a wide variety of different sources toextract useful substances from the materials, and to provide partiallydegraded materials which function as input to further processing stepsand/or sequences.

In one example, a first material that includes cellulose having a firstnumber average molecular weight (first M_(n)) is pyrolyzed, e.g., byheating the first material in a tube furnace (in the presence or absenceof oxygen), to provide a second material that includes cellulose havinga second number average molecular weight (second M_(N)) lower than thefirst number average molecular weight. The second material (or the firstand second material in certain embodiments) is/are combined with amicroorganism (with or without acid or enzymatic hydrolysis) that canutilize the second and/or first material to produce a fuel that is orincludes hydrogen, an alcohol (e.g., ethanol or butanol, such as n-, secor t-butanol), an organic acid, a hydrocarbon or mixtures of any ofthese.

Since the second material has cellulose having a reduced molecularweight relative to the first material, and in some instances, a reducedcrystallinity as well, the second material is generally moredispersible, swellable and/or soluble in a solution containing themicroorganism, e.g., at a concentration of greater than 106microorganisms/mL. These properties make the second material moresusceptible to chemical, enzymatic and/or microbial attack relative tothe first material, which can greatly improve the production rate and/orproduction level of a desired product, e.g., ethanol, Pyrolysis can alsosterilize the first and second materials.

In some embodiments, the second number average molecular weight (secondM_(n),) is lower than the first number average molecular weight (firstM_(n),) by more than about 10 percent, e.g., 15, 20, 25, 30, 35, 40, 50percent, 60 percent, or even more than about 75 percent.

In some instances, the second material has cellulose that has ascrystallinity (C2) that is lower than the crystallinity (C1) of thecellulose of the first material. For example, (C2) can be lower than(C1) by more than about 10 percent, e.g., 15, 20, 25, 30, 35, 40, oreven more than about 50 percent.

In some embodiments, the starting crystallinity (prior to pyrolysis) isfrom about 40 to about 87.5 percent, e.g., from about 50 to about 75percent or from about 60 to about 70 percent, and the crystallinityindex after pyrolysis is from about 10 to about 50 percent, e.g., fromabout 15 to about 45 percent or from about 20 to about 40 percent.However, in certain embodiments, e.g., after extensive pyrolysis, it ispossible to have a crystallinity index of lower than 5 percent. In someembodiments, the material after pyrolysis is substantially amorphous.

In some embodiments, the starting number average molecular weight (priorto pyrolysis) is from about 200,000 to about 3,200,000, e.g., from about250,000 to about 1,000,000 or from about 250,000 to about 700,000, andthe number average molecular weight after pyrolysis is from about 50,000to about 200,000, e.g., from about 60,000 to about 150,000 or from about70,000 to about 125,000. However, in some embodiments, e.g., afterextensive pyrolysis, it is possible to have a number average molecularweight of less than about 10,000 or even less than about 5,000.

In some embodiments, the second material can have a level of oxidation(O2) that is higher than the level of oxidation (O1) of the firstmaterial. A higher level of oxidation of the material can aid in itsdispersability, swellability and/or solubility, further enhancing thematerials susceptibility to chemical, enzymatic or microbial attack. Insome embodiments, to increase the level of the oxidation of the secondmaterial relative to the first material, the pyrolysis is performed inan oxidizing environment, producing a second material that is moreoxidized than the first material. For example, the second material canhave more hydroxyl groups, aldehyde groups, ketone groups, ester groupsor carboxylic acid groups, which can increase its hydrophilicity.

In some embodiments, the pyrolysis of the materials is continuous. Inother embodiments, the material is pyrolyzed for a pre-determined time,and then allowed to cool for a second pre-determined time beforepyrolyzing again.

Oxidation of the Feedstock Materials

One or more oxidative processing sequences can be used to processcarbon-containing materials from a wide variety of different sources toextract useful substances from the materials, and to provide partiallydegraded and/or altered material which functions as input to furtherprocessing steps and/or sequences.

In one method, a first material that includes cellulose having a firstnumber average molecular weight (first M_(n)) and having a first oxygencontent (O1) is oxidized, e.g., by heating the first material in astream of air or oxygen-enriched air, to provide a second material thatincludes cellulose having a second number average molecular weight(second M_(n)) and having a second oxygen content (O2) higher than thefirst oxygen content (O1).

Such materials can also be combined with a solid and/or a liquid. Theliquid and/or solid can include a microorganism, e.g., a bacterium,and/or an enzyme. For example, the bacterium and/or enzyme can work onthe cellulosic or lignocellulosic material to produce a fuel, such asethanol, or a coproduct, such as a protein. Fuels and coproducts aredescribed in FIBROUS MATERIALS AND COMPOSITES,” U.S. application Ser.No. 11/453,951, filed Jun. 15, 2006. The entire contents of each of theforegoing applications are incorporated herein by reference.

In some embodiments, the second number average molecular weight is notmore 97 percent lower than the first number average molecular weight,e.g., not more than 95 percent, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45,40, 30, 20, 12.5, 10.0, 7.5, 5.0, 4.0, 3.0, 2.5, 2.0 or not more than1.0 percent lower than the first number average molecular weight. Theamount of reduction of molecular weight will depend upon theapplication. For example, in some preferred embodiments that providecomposites, the second number average molecular weight is substantiallythe same as the first number average molecular weight. In otherapplications, such as making ethanol or another fuel or coproduct, ahigher amount of molecular weight reduction is generally preferred.

In some embodiments in which the materials are used to make a fuel or acoproduct, the starting number average molecular weight (prior tooxidation) is from about 200,000 to about 3,200,000, e.g., from about250,000 to about 1,000,000 or from about 250,000 to about 700,000, andthe number average molecular weight after oxidation is from about 50,000to about 200,000, e.g., from about 60,000 to about 150,000 or from about70,000 to about 125,000. However, in some embodiments, e.g., afterextensive oxidation, it is possible to have a number average molecularweight of less than about 10,000 or even less than about 5,000.

In some embodiments, the second oxygen content is at least about fivepercent higher than the first oxygen content, e.g., 7.5 percent higher,10.0 percent higher, 12.5 percent higher, 15.0 percent higher or 17.5percent higher. In some preferred embodiments, the second oxygen contentis at least about 20.0 percent higher than the first oxygen content ofthe first material. Oxygen content is measured by elemental analysis bypyrolyzing a sample in a furnace operating at 1300° C. or higher. Asuitable elemental analyzer is the LECO CFINS-932 analyzer with aVTF-900 high temperature pyrolysis furnace.

Generally, oxidation of a material occurs in an oxidizing environment.For example, the oxidation can be effected or aided by pyrolysis in anoxidizing environment, such as in air or argon enriched in air. To aidin the oxidation, various chemical agents, such as oxidants, acids orbases can be added to the material prior to or during oxidation. Forexample, a peroxide (e.g., benzoyl peroxide) can be added prior tooxidation.

Some oxidative methods of reducing recalcitrance employ Fenton orFenton-type chemistry. Such methods are disclosed, for example, in U.S.application Ser. No. 12/639,289, filed Dec. 16, 2009, the completedisclosure of which is incorporated herein by reference,

Exemplary oxidants include peroxides, such as hydrogen peroxide andbenzoyl peroxide, persulfates, such as ammonium persulfate, activatedforms of oxygen, such as ozone, permanganates, such as potassiumpermanganate, perchlorates, such as sodium perchlorate, andhypochlorites, such as sodium hypochlorite (household bleach),

In some situations, pH is maintained at or below about 5.5 duringcontact, such as between 1 and 5, between 2 and 5, between 2.5 and 5 orbetween about 3 and 5. Conditions can also include a contact period ofbetween 2 and 12 hours, e.g., between 4 and 10 hours or between 5 and 8hours. In some instances, conditions include not exceeding 300° C.,e.g., not exceeding 250, 200, 150, 100 or 50° C. In special desirableinstances, the temperature remains substantially ambient, e.g., at orabout 20-25° C.

In some desirable embodiments, the one or more oxidants are applied to afirst cellulosic or lignocellulosic material and the one or morecompounds as a gas, such as by generating ozone in-situ by irradiatingthe first cellulosic or lignocellulosic material and the one or morecompounds through air with a beam of particles, such as electrons.

In particular desirable embodiments, a first cellulosic orlignocellulosic material is firstly dispersed in water or an aqueousmedium that includes the one or more compounds dispersed and/ordissolved therein, water is removed after a soak time (e.g., loose andfree water is removed by filtration), and then the one or more oxidantsare applied to the combination as a gas, such as by generating ozonein-situ by irradiating the first cellulosic or lignocellulosic and theone or more compounds through air with a beam of particles, such aselectrons (e.g., each being accelerated by a potential difference ofbetween 3 MeV and 10 MeV). Soaking can open up interior portions tooxidation.

In some embodiments, the mixture includes one or more compounds and oneor more oxidants, and a mole ratio of the one or more compounds to theone or more oxidants is from about 1:1000 to about 1:25, such as fromabout 1:500 to about 1:25 or from about 1:100 to about 1:25.

In some desirable embodiments, the mixture further includes one or morehydroquinones, such as 2,5-dimethoxyhydroquinone (DMHQ) and/or one ormore benzoquinones, such as 2,5-dimethoxy-1,4-benzoquinone (DMBQ), whichcan aid in electron transfer reactions.

In some desirable embodiments, the one or more oxidants areelectrochemically-generated in-situ. For example, hydrogen peroxideand/or ozone can be electro-chemically produced within a contact orreaction vessel.

Other Processes to Solubilize, Reduce Recalcitrance or to Functionalize

Any of the processes of this paragraph can be used alone without any ofthe processes described herein, or in combination with any of theprocesses described herein (in any order): steam explosion., acidtreatment (including concentrated and dilute acid treatment with mineralacids, such as sulfuric acid, hydrochloric acid and organic acids, suchas trifluoroacetic acid), base treatment (e.g., treatment with lime orsodium hydroxide), UV treatment, screw extrusion treatment (see, e.g.,U.S. patent application Ser. No. 12/417,723, filed Nov. 18, 2008,solvent treatment (e.g., treatment with ionic liquids) and freezemilling (see, e.g., U.S. Pat. No. 7,900,857)

Production of Fuels and/or Other Products by Bioprocessing

After one or more of the processing steps discussed above have beenperformed on the biomass, the complex carbohydrates contained in thecellulose and hemicellulose fractions can be processed into sugars usinga saccharification process, as discussed above.

The resulting sugar solution can be converted into a variety of productsby fermentation, such as alcohols, e.g., ethanol, or organic acids. Theproduct obtained depends upon the microorganism utilized and theconditions under which the bioprocessing occurs. These steps can beperformed, for example, utilizing the existing equipment of thecorn-based ethanol manufacturing facility.

Generally, fermentation utilizes various microorganisms. The sugarsolution produced. by saccharification of lignocellulosic materials willgenerally contain xylose as well as glucose. It may be desirable toremove the xylose, e.g., by chromatography, as some commonly usedmicroorganisms (e.g., yeasts) do not act on xylose. The xylose may becollected and utilized in the manufacture of other products, e.g., thesweetener Xylitol. The xylose may be removed prior to or after deliveryof the sugar solution to the manufacturing facility where fermentationwill be performed.

The microorganism can be a natural microorganism or an engineeredmicroorganism. For example, the microorganism can be a bacterium, e.g.,a cellulolytic bacterium, a fungus, e.g., a yeast, a plant or a protist,e.g., an algae, a protozoa or a fungus-like protist, e.g., a slime mold.When the organisms are compatible, mixtures of organisms can beutilized. The microorganism can be an aerobe or an anaerobe. Themicroorganism can be a homofermentative microorganism (produces a singleor a substantially single end product). The microorganism can be ahomoacetogenic microorganism, a homolactic microorganism, a propionicacid bacterium, a butyric acid bacterium, a succinic acid bacterium or a3-hydroxvpropionic acid bacterium. The microorganism can be of a genusselected from the group Clostridium, Lactobacillus, Moorella,Thermoanaerobacter, Proprionibacterium, Propionispera,Anaerobiospirillum, and Bacteriodes. In specific instances, themicroorganism can be Clostridium formicoaceticum, Clostridium butyricum,Moorella thermoacetica, Thermoanaerobacter kivui, Lactobacillusdelbrukii, Propionibacterium acidipropionici, Propionispera arboris,Anaerobiospirillum succinicproducens, Bacteriodes amylophilus orBacteriodes ruminicola. For example, the microorganism can be arecombinant microorganism engineered to produce a desired product, suchas a recombinant Escherichia coli transformed with one or more genescapable of encoding proteins that direct the production of the desiredproduct is used (see, e.g., U.S. Pat. No. 6,852,517, issued Feb. 8,2005).

Carboxylic acid groups generally lower the pH of the fermentationsolution, tending to inhibit fermentation with some microorganisms, suchPichia stipitis. Accordingly, it is in some cases desirable to add baseand/or a buffer, before or during fermentation, to bring up the pH ofthe solution. For example, sodium hydroxide or lime can be added to thefermentation medium to elevate the pH of the medium to range that isoptimum for the microorganism utilized.

Fermentation is generally conducted in an aqueous growth medium, whichcan contain a nitrogen source or other nutrient source, e.g., urea,along with vitamins and trace minerals and metals. It is generallypreferable that the growth medium be sterile, or at least have a lowmicrobial load, e.g., bacterial count. Sterilization of the growthmedium may be accomplished in any desired manner. However, in preferredimplementations, sterilization is accomplished by irradiating the growthmedium or the individual components of the growth medium prior tomixing. The dosage of radiation is generally as low as possible whilestill obtaining adequate results, in order to minimize energyconsumption and resulting cost. For example, in many instances, thegrowth medium itself or components of the growth medium can be treatedwith a radiation dose of less than 5 Mrad, such as less than 4, 3, 2 or1 Mrad. In specific instances, the growth medium is treated with a doseof between about 1 and 3 Mrad.

Products by Chemical Reactions

FIG. 3 shows various transformation of xylose (3 a) in its open chainaldehyde form to products. Chemical transformations using, for example,catalysts are useful to convert sugars (e.g., xylose) derived frombiomass material as described herein into useful organic products. Theproducts can be directly converted to a product (e.g., furfural 3 b) orcan be converted through various intermediates as depicted in FIG. 3.Prior to conversion the, sugar (e.g., xylose) can be isolated,concentrated, and/or purified from the saccharified biomass usingvarious methods such as distillation, crystallization, precipitation,chromatography (e.g., simulated moving bed chromatography),centrifugation, settling, sedimentation, floatation, fermentation (e.g.,fermentation of other sugars such as glucose to a greater degree thanthe xylose) or combinations of these and/or other methods.

Chemical conversions can be performed in the same tank as thesaccharification (e.g., in situ right after saccharification) ortransferred (optionally with a purification step) to a second tank forchemical reaction. For example the tank for the chemical reaction can beequipped with temperature control units, mixing units, may be made towithstand corrosive or dissolving solvents, made to withstand higherthan atmospheric pressure. These chemical conversions can also be donein a continuous fashion (e.g., using a tube reactor, continuous stirredtank reactor) or semi-continuous fashion.

Examples of chemical conversion of xylose to furfural and subsequentproducts is shown if FIG. 3. While several of the products do not haveany carbon atom that has stereochemistry, products 3 d and 3 f do havestereocenters. The chemistries envisaged here can lead to purestereoisomers or D,L mixtures that could be resolved.

The chemical conversion of xylose (3 a) to methytetrahydrofuran (3 f)can be done in several steps. In a first step xylose (3 a) is dehydratedand cyclization to furfural (3 b) alternatively calledfurancarboxaldehyde which is an oily, colorless heterocyclic aldehyde.Several catalyst systems can transform xylose to furfural successfully.Some possible acidic systems are Zeolite acidified with H₃PO₄/H₂SO₄;Sulfonic acid, Silica surface grafted; 1-Methylimidazole, i-BuC(═O)Me;KI, KCl; 1-alkyl-3-methylimidazolium ionic liquids; NaCl, SiO₂, ZeoliteBeta, Sulfonic acid functionalized mesoporous silica MCM-41;perfluorinatecl sulfonic acid resins (Nafion®), acidic clays, FeCl₃,NaCl; Mesoporous silica supported; SBA-15 supported sulfonic acid, SiO₂,H₂SO₄; Tetraethyl orthosilicate, 3-(mercaptopropyl) trimethoxy silane,LaCl₃; Microporous silicoaluminophosphate; ZrO₂, Tungstate; LSC resin;Al₂O₃, tungstate; TiO₂ sulfonated; V₂O₅, H₃PO₄; ZrO₂, Al₂O₃, (NH₄)SO₄;SiO₂, MgCl₂; HCl, Microwave irradiation; Amberlyst 15; Cs₂CO₃, SiO₂.These reactions can be performed under higher temperatures and/or highpressure.

Furfural is used as a solvent for refining lubricating oils, as afungicide and weed killer. Furfural is also a chemical intermediate inthe production of methyltetrahydrofuran (30 which is an importantindustrial solvent. In addition, furfural (3 b) can serve as a buildingblock for other potential transportation fuels. Furfural is an importantrenewable, non-petroleum based, chemical feedstock. It is highlyregarded for its thermosetting properties, physical strength andcorrosion resistance. It is consumed by the chemical industry as anintermediate product in synthesizing chemical products such as nylon,lubricants, solvents, adhesives, medicines and plastics.

Furfural is also a chemical intermediate to furfuryl alcohol sincereduction of the aldehyde group of furfural provides furfuryl alcohol (3c). Furfuryl alcohol is also a useful chemical intermediate and can bedearomatized to tetrahydrofurfuryl alcohol (3 d). Some of the industrialprocesses are listed below:

In a two-step process, biomass (e.g., plant materials) containing xyloseis mixed with an acid (e.g., dilute sulphuric acid) or a saccharifyingenzyme, producing sugars including xylose. The xylose is cyclohydratedlosing three moles of water to furfural in the second step, e.g., withan acid (e.g., dilute sulphuric acid optionally from the first step).The product can be recovered by steam distillation from a mixture ofacid and undigested biomass.

Furfural (3 b) is a versatile chemical intermediate and can be used tomake other furan chemicals, such as furoic acid, via oxidation, andfuran (3 g) itself via palladium catalyzed vapor phase decarbonylation.Furfuryl alcohol (3 c) can be manufactured by the catalytic reduction offurfural. Reduction of the furfural aldehyde group (3 b) can yieldfurfuryl alcohol. For example, the aldehyde can be reduced by usingNaBH₄ in MeOH in one hour with (e.g., yielding greater than 10% product,e.g., greater than 20%, greater than 30%, greater than 40%, greater than50%, greater than 60%, greater than 70%, greater than 80%). Otherreactants that can be used for this transformation include, FeCl₃,ZnCl₂; NiCl₂, Al₂O₃, Pt, TiO₂, SiO₂; NH⁴⁺.HCO²⁻, Ni; [RhCl(COD)]₂; CuO,Cr₂O₃, SiO₂.

Furfuryl alcohol (3 c), also called 2-furylmethanol or 2-furancarbinol 3c), is an organic compound containing a furan substitute hydroxymethylgroup. It is a clear colorless liquid when pure, but becomes ambercolored upon prolonged standing. It possesses a faint burning odor and abitter taste. It is miscible with but unstable in water. It is solublein common organic solvents. Upon treatment with acids, heat and/orcatalysts, furfuryl alcohol can be made to polymerize into a resin,poly(furfuryl alcohol). It also can be used as a solvent and as aningredient in the manufacture of various chemical products such asfoundry resins, adhesives, and wetting agents.

Furfuryl alcohol (3 c) has been used in rocketry as a fuel, whichignites with white fuming nitric acid or red fuming nitric acidoxidizer. Because of its low molecular weight, furfuryl alcohol (3 c)can impregnate the cells of wood, where it can be polymerized and bondedwith the wood by heat, radiation, and/or catalysts or additionalreactants (e.g., by the methods disclosed in U.S. Pat. No. 7,846,295 thefull disclosure incorporated herein by reference). The treated wood hasimproved moisture stability, dimensional stability, hardness, microbialdecay resistance and insect resistance; catalysts can include zincchloride, citric or formic acid, or borates.

Dearomatization of furfuryl alcohol (3 c) to tetrahydrofurfuryl alcohol(3 d) can be performed using several metal catalysts under highpressures (e.g., between 10 and 8000 psi) and temperatures (e.g., from50 to 400° C.). For example, catalysts can be selected from: Hectoritesupported Ru nanoparticles; nickel boride/SiO₂; Skeleton Ni; L-Serine,Alginic acid, platinum complex; Na₂O, ZnO, NiO, Al₂O₃; Ni, Al, Mo, Si,Ca; Rh—PPh₃ complex; RuO₂; Ru; Ru/TiO₂; Al/Ni alloy; nickel boride,nickel/cobalt boride; NiO, amongst others. The hydrogenation reactionstake from minutes (or hours) to a day (or several days).Tetrahydrofurfuryl alcohol is a hygroscopic, colorless liquid, misciblewith water; used as a solvent for resins, in leather dyes, and in nylon.Tetrahydrofurfuryl alcohol can be used as a nonhazardous solvent inagricultural formulations and as an adjuvant to help herbicidespenetrate the leaf structure. Dihydropyran can be prepared by thedehydration of tetrahydrofurfuryl alcohol over alumina at 300-400° C.

2-Methyltetrahydrofuran (30 is an organic compound with the molecularformula CH₃C₄H₇O. It is a highly flammable mobile liquid. It is mainlyused as a replacement for THF in specialized applications for its betterperformance in those applications, e.g., to obtain higher reactiontemperatures, or easier separations due to the solubility, changedacidity and changed donor properties of the ring oxygen of the2-methyltetrahydrofuran. It also is used in the electrolyte formulationfor secondary lithium electrodes and as a component in alternativefuels.

It is a valued solvent for low temperature reactions.2-Methyltetrahydrofuran forms a glass, which does not crystallize, andis frequently used as a solvent for spectroscopic studies at −196° C.Methyltetrahycirofuran has a stereocenter alpha to the oxygen. ‘Themethyltetrahydrofuran produced by these chemistries may be a 50:50mixture of stereoisomers or enriched in either enantiomer.

Other common uses of 2-methyltetrahydrofuran is as a solvent forGrignard reagents used in organometallic and biphasic chemicalprocesses, because of the oxygen atom's ability to coordinate to themagnesium ion component of the Grignard reagent, or to azeotropicallydry products. The use of 2-methyltetrahydrofuran provides very cleanorganic-water phase separations. It is a popular, but costliersubstitute for tetrahydrofuran.

2-Methyltetrahydrofuran has been approved by the United StatesDepartment of Energy as an additive to gasoline. Furfural and otherpartially hydrogenated/reduced furyl compounds between it and2-methyltetrahydrofuran (furfuryl alcohol, methylfuran, tetrahydrofurylalcohol) have a tendency to polymerize and are quite volatile.2-methyltetrahydrofuran itself, however, is more stable and lessvolatile, and thus is suitable for use as a motor fuel.

2-Methyltetrahydrofuran has one stereocenter, so it exists in twoenantiomeric forms. In some processes involving hydrogenation a racemicmixture of the two enantiomers is formed. The asymmetric synthesis of(S)-(+)-2-methyltetrahydrofuran can be achieved by using chiralcatalytic hydrogenation, e,g., using supported catalysts such aswool-rhodium complex. 158. The conversion of 3 c to 3 e involveshydrogenolysis. 3 e can be converted to 3 f by vapor phase hydrogenationusing Raney Ni under 200° C. Furfural (3 b) can be catalyticallyconverted to Furan (3 g) by metal complexes. For examples, the reactionscan be made to proceed via metal-acyl hydrides. Cu/Mo fixed bed complexcan catalyze this conversion under high pressures and temperatures(e.g., between 10 and 20000psi and 50 to 400° C.) with continuous flowof hydrogen. Catalyst complexes of Pd and Ni have also been used butthey have proven to be less selective (leading to ring opening and C4compounds). The hydrogenation of Furan (3 g) to tetrahydrofuran (3 h)can be performed under high pressure and temperature under hydrogenusing metal based catalysts such as Raney Ni, Ru and Pt

The furfural-derived products can be the product of a multiple stepreaction scheme. The intermediates along the reaction scheme may beisolated before subsequent reactions. For example, the furfural can beisolated and purified prior to conversion of furfural alcohol.

EXAMPLES

Unless otherwise noted the chemicals were obtained from Alfa Chemical,Kings Point New York; Sigma Aldrich Chemical, St Louis, Mo.

Example I Xylose Conversion to Furfural with Acetic Acid

To a 1-Liter pressure vessel equipped with a vent condenser (Parrstainless steel reactor, Parr instrument Company, Moline Ill.) 20 gramsof xylose, 0.2mL of glacial acetic acid and 400 mL of water was added.The vessel was heated to 185° C. and liquids distilled from the reactor.The total heating time was two hours. Most of the furfural was recoveredfrom the distillate. The furfural yield was determined by gaschromatography to be 39 percent.

Example II Xylose Conversion to Furfural

To a 1-Liter pressure vessel equipped with a vent condenser (Parrstainless steel reactor, Parr Instrument Company, Moline Ill.) 50 gramsof xylose, and 500 mL of water was added. The reactor was heated to 185°C., agitated at 350 rpm and the pressure was 145 psig. The furfuralyield was 45 percent.

Example III Xylose Conversion to Furfural, Calcium Chloride Added

To a 1-Liter pressure vessel equipped (Parr stainless steel reactor,Parr Instrument Company, Moline 30 grams of xylose (from CascadeAnalytical Reagents and Biochemical, Corvallis, Oreg.), 300mL ofmethyltetrahydrofuran, calcium chloride, 30 grams and 150 mL of waterwas added. The reactor was heated to 200° C. for four hours. Thefurfural yield was 55 percent.

Example IV Xylose Conversion to Furfural; Continuous Processing

Xylose was dissolved in water at 0.66 moles/liter. This solution waspumped through a heated tubular reactor. At 180° C. the furfural yieldwas less than 5 percent. At 200° C. the yield was13% at a 10 minuteresidence time. At 220° C. at a 10 min residence time reached 40%.

Other than in the examples herein, or unless otherwise expresslyspecified, all of the numerical ranges, amounts, values and percentages,such as those for amounts of materials, elemental contents, times andtemperatures of reaction, ratios of amounts, and others, in thefollowing portion of the specification and attached claims may be readas if prefaced by the word “about” even though the term “about” may notexpressly appear with the value, amount, or range. Accordingly, unlessindicated to the contrary, the numerical parameters set forth in thefollowing specification and attached claims are approximations that mayvary depending, upon the desired properties sought to be obtained by thepresent invention. At the very least, and not as an attempt to limit theapplication of the doctrine of equivalents to the scope of the claims,each numerical parameter should at least be construed in light of thenumber of reported significant digits and by applying ordinary roundingtechniques.

Notwithstanding that the numerical ranges and parameters setting forththe broad scope of the invention are approximations, the numericalvalues set forth in the specific examples are reported as precisely aspossible. Any numerical value, however, inherently contains errornecessarily resulting from the standard deviation found in itsunderlying respective testing measurements. Furthermore, when numericalranges are set forth herein, these ranges are inclusive of the recitedrange end points (e.g., end points may be used). When percentages byweight are used herein, the numerical values reported are relative tothe total weight.

Also, it should be understood that any numerical range recited herein isintended to include all sub-ranges subsumed therein. For example, arange of “1 to 10” is intended to include all sub-ranges between (andincluding) the recited minimum value of I and the recited maximum valueof 10, that is, having a minimum value equal to or greater than 1 and amaximum value of equal to or less than 10, The terms “one,” “a,” or “an”as used herein are intended to include “at least one” or “one or more,”unless otherwise indicated.

Any patent, publication, or other disclosure material, in whole or inpart, that is said to be incorporated by reference herein isincorporated herein only to the extent that the incorporated materialdoes not conflict with existing definitions, statements, or otherdisclosure material set forth in this disclosure. As such, and to theextent necessary, the disclosure as explicitly set forth hereinsupersedes any conflicting material incorporated herein by reference.Any material, or portion thereof, that is said to be incorporated byreference herein, but which conflicts with existing definitions,statements, or other disclosure material set forth herein will only beincorporated to the extent that no conflict arises between thatincorporated material and the existing disclosure material.

While this invention has been particularly shown and described withreferences to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the scope of the inventionencompassed by the appended claims.

What is claimed is:
 1. A method for processing biomass, the methodcomprising: irradiating biomass to reduce the recalcitrance of thebiomass; saccharifying the irradiated biomass with one or more enzymesto produce a first sugar composition comprising xylose and glucose;fermenting the first sugar composition to produce a second sugarcomposition comprising xylose and glucose, wherein the concentration ofxylose in the second sugar composition is increased relative to thefirst sugar composition; isolating the xylose from the second sugarcomposition; converting the isolated xylose to furfural; and convertingthe furfural to a furoic acid.
 2. The method of claim 1, whereinisolating the xylose from the second sugar composition comprises one ormore isolation method selected from the group consisting ofdistillation, crystallization, precipitation, sedimentation,chromatography, centrifugation, settling, sedimentation, and floatation.3. The method of claim, 1 wherein the biomass comprises one or more ofpaper, paper product, wood, wood-related material, particle board,grass, rice hulls, bagasse, cotton, jute, hemp, flax, bamboo, wheatstraw, sisal, abaca, straw, corn cobs, corn stover, coconut hair, algae,seaweed, altered cellulose, regenerated cellulose, microbial material,municipal waste, waste from paper processing, newspaper, kraft paper,corrugated paper, cotton, rags, and animal waste.
 4. The method of claim1, wherein the biomass is densified before irradiating.
 5. The method ofclaim 1, further comprising treating the biomass to reduce itsrecalcitrance, before or after irradiating, with one or more ofmechanically treating, sonicating, pyrolyzing, oxidizing, steamexploding, and chemically treating.
 6. The method of claim 1, whereinthe biomass is irradiated with one or more of microwave energy,ultraviolet rays, infrared radiation and ionizing radiation.
 7. Themethod of claim 1, wherein the biomass is irradiated with one or more ofalpha particles, protons, gamma rays and X-rays.
 8. The method of claim1, wherein the biomass is irradiated with ions heavier than electrons.9. The method of claim 1, wherein converting the furfural to the furoicacid comprises an oxidation.
 10. The method of claim 1, wherein thebiomass is irradiated with ionizing radiation delivered by electronbeam.
 11. The method of claim 10, wherein the ionizing radiation isdelivered at a dosage that is between 10 Mrad and 200 Mrad.
 12. Themethod of claim 10, wherein the electron beam has a power between 0.5and 10 MeV.
 13. The method of claim 1, wherein the biomass is irradiatedwith two or more radiation sources.
 14. The method of claim 1, whereinthe biomass is treated to reduce its recalcitrance, before or afterirradiating, by sonicating in an oxidizing medium.
 15. The method ofclaim 1, further comprising partially or completely saccharifying thebiomass during transporting to a manufacturing plant.
 16. The method ofclaim 1, wherein the biomass is saccharified partially or completely ina tank.
 17. The method of claim 16, wherein the contents of the tank arejet mixed.
 18. The method of claim 16, wherein conversion of the xyloseto furfural occurs in the tank.
 19. The method of claim 18, whereinconversion of the xylose to furfural occurs in a continuous process. 20.The method of claim 1, wherein the one or more enzymes comprise aligninase, a xylanase, a hemicellulase, an endoglucanase, acellobiohydrolase, or a beta-glucosidase.
 21. The method of claim 1,wherein the one or more enzymes comprise an enzyme complex comprisingxylanase.
 22. The method of claim 1, wherein the sugars are at aconcentration of at least 40% by weight in the first sugar composition.23. The method of claim 1, further comprising isolating the glucose. 24.The method of claim 1, further comprising isolating the furfural. 25.The method of claim 1, wherein conversion of the xylose to furfural iscatalyzed by a Lewis acid.